drm/rockchip: cdn-dp: select bridge for cdp-dp

Select drm bridge connector when building cdp-dp.
This was missed in previous commit causing build failure.

Fixes: afbbca2 ("drm/rockchip: cdn-dp: Convert to drm bridge")
Signed-off-by: Rudi Heitbaum <rudi@heitbaum.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/aJrlUzV1u4i65NRe@8eba3d7b3083

Author: heitbaum

drivers/gpu/drm/rockchip/Kconfig

@@ -53,6 +53,7 @@ config ROCKCHIP_CDN_DP
 	bool "Rockchip cdn DP"
 	depends on EXTCON=y || (EXTCON=m && DRM_ROCKCHIP=m)
 	select DRM_DISPLAY_HELPER
+	select DRM_BRIDGE_CONNECTOR
 	select DRM_DISPLAY_DP_HELPER
 	help
 	  This selects support for Rockchip SoC specific extensions